Magnetron-sputtered BiVO 4 photoanodes for solar water splitting: from thin-film growth to photoelectrochemical performance

Photoelectrochemical (PEC) water splitting for zero-emission hydrogen production has emerged as a promising and sustainable energy conversion strategy and has been extensively investigated over the past decades. A major challenge remains the development of efficient photoelectrodes capable of driving water oxidation with high quantum efficiency under solar illumination. Among candidate materials, bismuth vanadate (BiVO4) has attracted considerable attention due to its narrow band gap, favorable band-edge positions, and relatively good PEC stability under neutral or mild alkaline conditions. With growing interest in BiVO4, scalable and controllable deposition techniques are essential to validate its potential for large-area PEC fuel generation. Magnetron sputtering has proven to be a versatile method for fabricating high-quality BiVO4 thin films, enabling homogeneous large-area deposition, excellent conformality, and precise stoichiometric control. This review provides a comprehensive overview of sputtered BiVO4 photoanodes for PEC water-splitting applications. It discusses structural and optoelectronic properties, critically evaluates sputtering parameters influencing film performance, and examines modification strategies, including heterojunctions, elemental doping, and co-catalyst integration, to enhance charge separation and reaction kinetics. Finally, key challenges and future perspectives toward scalable PEC device implementation are outlined.